A Sukkah is a ceremonial Jewish structure that is erected outdoors to shelter people during certain religious holidays. The prior structures used as Sukkahs have suffered from problems when rain falls during the time people are inside the structure.
The prior Sukkah structures have generally been covered with retractable flat canvas covers. The problem with those structures is that when the rainfall is heavy the structure will sag in the middle from the weight of the water. In addition, these canvas covers can become saturated with water and begin to leak through the material into the interior of the structure. If enough rain is present on top of those covers, the water may begin falling over the edges into the structure itself with the occupants of the structure getting wet. When the canvas cover is closed, ventilation will be poor. In addition, the roof cover generally can be retracted only leaving the interior of Sukkah the structure itself. When the roof cover is retracted after the rain, the water on top of the cover generally falls at least partly inside the structure again getting the occupants wet.